SYNTHESIS AND CHARACTERIZATION OF GOLD(I) THIOLATES, SELENOLATES, AND TELLUROLATES - X-RAY CRYSTAL-STRUCTURES OF AU4[TEC(SIME3)3]4, AU4[SC(SIME3)3]4, AND PH3PAU[TEC(SIME3)3]

We describe the preparation of a series of homoleptic gold(I) chalcogenolates of empirical formula Au[ER] (E = S, Se, Te; R = C(SiMe3)3, Si(SiMe3)3, Ge(SiMe3)3), by reaction of the appropriate lithium salts, LiER, with AuCl(THT) (THT = tetrahydrothiophene) in benzene or hexane. Metatheses between LiER and Ph3PAuCl in diethyl ether afford the (triphenylphosphine)gold(I) complexes Ph3PAu[ER]. The derivatives Au4[TeC(SiMe3)3]4 and Ph3PAu[TeC(SiMe3)3] are the first gold tellurolates reported, and both have been structurally characterized by X-ray crystallography. Au4[TeC(SiMe3)3]4 crystallizes at ambient temperatures from warm benzene in the space group P2(1)2(1)2(1) with a = 15.295(2) angstrom, b = 16.011(2) angstrom, c = 29.971(6) angstrom, V = 7340(4) angstrom3, d(calcd) = 2.013 g cm-3, and Z = 4. Ph3PAu[TeC(SiMe3)3] crystallizes from ether at -40-degrees-C in the space group P2(1)/n with a = 9.748(3) angstrom, b = 21.472(5) angstrom, c = 15.684(3) angstrom, beta = 100.37(2)degrees, V = 3229(1) angstrom3, d(calcd) = 1.683 g cm-3, and Z = 4. The thiolate analogue Au4[SC(SiMe3)3]4 has also been structurally characterized for comparison: this crystallizes from hexane at -40-degrees-C in the space group P2(1)/c with a = 14.976(2) angstrom, b = 18.99(1) angstrom, c = 27.622(5) angstrom, beta = 102.83(2)degrees, V = 7659(5) angstrom3, d(calcd) = 1.598 g cm-3, and Z 4; one molecule of disordered hexane is associated with each tetramer in the asymmetric unit.